Dark Field X-ray Microscopy[1]} (DFXM) is a full-field x-ray imaging technique similar to x-ray topography[2]}, [3]}. However, unlike the latter, DFXM utilizes an x-ray objective lens placed between the sample and the detector to create a magnified image and can therefore achieve a spatial resolution better than the detector pixel size.
The spatial band width is limited by the small numerical aperture (NA \({\approx }10^{-3}\) ) of this objective lens. Compared to classical x-ray topography, this provides angular resolution of the scattered beam direction [4]}, which makes it possible to quantitatively measure strains and rotations of the crystal lattice by sequentially collecting images while rotating the sample and moving the objective lens.
